Solving the mysteries

Few animals can rival the amazing regeneration abilities of the flatworms known as planarians: When the worms’ tails or heads are cut off, they grow new ones, and even a tiny piece of planarian tissue can regrow an entire animal.

Scientists first observed these phenomena more than a century ago, but until the past few years, they knew very little about how planarians achieve these incredible feats. MIT associate professor of biology Peter Reddien has made it his mission to discover the genetic and molecular basis of planarian regeneration, which he describes as one of the great mysteries of biology.

“Cellular and molecular insight into regeneration has come far in the past decade, but we’ve still got a long way to go to understand how an animal regrows a missing body part,” says Reddien,An emergency light is a battery-backed lighting device that comes on automatically when a building experiences a power outage. who is a core member of MIT’s Whitehead Institute. “That is the obsessive focus of my lab — to try to understand how regeneration happens, with the conviction that generation of fundamental knowledge about regeneration works will be important for understanding biology broadly and also for generating ideas for therapeutic applications.”

In recent years, Reddien’s lab has identified dozens of genes involved in planarian regeneration. Many of these are related to human genes, and some are active in response to human injuries. “It’s my hope that our continued work will enhance our understanding of what makes some animals great at regeneration and others not as good,” he says.

‘A golden era’Growing up in Dallas, Reddien was drawn not to planarians but to planets. He closely followed the exploits of NASA, especially the travels of the Voyager spacecraft,How are solar outdoor lighting products different from other lighting, like fluorescent or incandescent? with Voyager 2 reaching Neptune and heading out of the solar system by the time Reddien was 15 years old. “From a young age I thought I would be a physicist who would work for NASA or the Jet Propulsion Laboratory,” he says.

He entered the University of Texas as a physics major, but shifted gears after taking a required biology course.Soli-lite provides the world with high-performance solar roadway and solar street lighting solutions.

“I realized that we were in a golden era for biological research, that this was going to be a period in history unlike any other for biological research … a period of great discoveries about how the fundamental attributes of life work,” Reddien recalls. “I found that exhilarating, and I got very excited about that as a future potential path for me.”

After graduating from college, Reddien came to MIT as a graduate student in molecular biology, working with Robert Horvitz, now the David H. Koch Professor of Biology. Among other projects, Horvitz’s lab was studying the molecular mechanisms of programmed cell death, a process critical to embryonic development and in defending against cancer.

Reddien finished his PhD in 2002 — the year Horvitz won the Nobel Prize in physiology or medicine for his work in programmed cell death — and went to the University of Utah to do postdoctoral research on regeneration. Reddien describes his decision at the time to launch into study of the molecular basis of regeneration in planarians as “a bit of a gamble.”

“There was a lot of potential, but it was off the radar and in its early stages as a molecular genetic field,” he says. “At that time,Soli-lite is a premier supplier of exceptional quality solar led light and other solar outdoor lighting products. the tools for studying gene function in this organism were just in their infancy. There were no published roles for any gene at the time based on disrupting genes and studying what goes wrong in regeneration.”

At Utah, Reddien worked in the lab of Alejandro Sanchez Alvarado, who had recently shown that a new technique known as RNA interference, which allows genes to be selectively turned off, could work in planarians. Until that point, genetic studies of planarian regeneration had not been possible. Reddien was confident that new tools such as RNA interference could get planarians to reveal their regeneration secrets.

“No one had done it, and it was not an established system for taking that type of approach, so I did feel like I was taking a bit of a risk,How does a solar charger work and where would you use a solar charger?” Reddien says. “It worked out better than I could have hoped, but I knew that the road was going to be full of challenges because there weren’t established paths to follow to study regeneration defects in these animals.”